Catapult device for launching aerial machines



July 18, 1950 J. FIEUX CATAPULT DEVICE FOR LAUNCHING AERIAL MACHINES Filed Dec. 29, 1939 2 Sheets-Sheet 1 attorneys July 18, 1950 J. FIEUX CATAPULT DEVICE FOR LAUNCHING AERIAL MACHINES Filed Dec. 29, 1939 2 Sheets-Sheet 2 Patented July 18, 1950 CATABULT DEVICE FOR LAUNCHING AERIAL MACHINES J can Fieux, Paris, France, vested in the Attorney encr of the nited Sta e Application December 29, 1939, Serial No. 311,678 In France December 30, 1938 6 Claims.

t is known that the launchin of gliders or aeroplanes by catapult at present gives rise to questions which are difiicult to solve both by rea son of the high speeds of departure which it is necessary to impart to masses which are becoming larger and larger and by reason of the necessity of having recourse in certain cases to means compatible with makeshift installations for braking the movementof the parts of the catapult to be retained after propulsion (launching carriage, cable, piston and the like).

Considerable efforts have already been made both to increase the conditions under which the forces applied to the elements to be launched are set up and to attenuate thereactions of all kinds which are exerted on the propelling means and on the sub-structure equipment. However, these efforts do not yet appear to have led to a simple and really satisfactory solution.

The catapult arrangements at present known are of what may be called the "simple traction type. These do not possess all the flexibility desirable for adapting the available effort to the efiective conditions of launching and braking which it is desired to produce. They necessitate in particular the use of auxiliary brakes for the progressive absorption of the kinetic energy of the carriage and of the propelling means. The power and the bulk of these brakes necessitate a sub-structure incompatible with the provision oi the makeshift installations which must be constructed in a short time on any kind of ground.

In addition, such arrangements do not lend themselves to the reversal of the direction of launching on the same track under acceptable conditions unless two braking sub-structures independent of one another have been-provided, each of which is only utilisable'for one direction of movement.

In practice. on the other hand, they do not permit of retaining, if desired, the whole of the propelled mass (carriage and its load), nor consequently o-f making working tests under conditions which actually approximate to the effective conditions during actual launching, employing a suitable ballast intended to remain integral with the carriage.

The present invention relates to an indirect or compound traction catapult device, which is characterised by the fact that there extend from the pulley-block system employed for multiplying, in any suitable manner, the speed of dis- Placement of the propelling element proper, two

' moving parts of a cable which join one another,

after having passed respectively over t-WO guide members disposed on either side of the launching track, in order to act on the carriage carried by the said track, in the same way as the cord. oi'a cross-bow acts on an arrow or projectile which it projects into space.

Such an arrangement aflords multiple-advanF tages which precisely overcome the disadvantages mentioned in the foregoing as being inherent in the use of simple traction arrangements.

Owing, on the one hand, to the figure symmetry of the two moving sides of the cable with respect to the axial plane of the launching track, and, on the other hand, to a certain symmetry of evolution of the compound traction, which is naturally attained in time with respect to the moment of the passage-of the carriage into align ment with the lateral guide members, the pressure of the gases being maintained in the work.- ing chamber of the catapult, a retaining'efiect comparable in power to the propelling effect is ensured under excellent conditions without the assistance of auxiliary brakes and regardless of the direction of launching.

It is sufiicient to dispose the lateral guide points at a suitable distance apart in order to reduce to anacceptable value the supplementary tension imparted'to the cable by the inertia of the var,- ious propelling members and in particular by the inertia of the two moving sides of the said cable, the winding speeds of which must nullify'one another, in order to change direction, at the moment of the passage of the carriage into alignment with the guide points.

It is to be noted that that distance between the guide points is never prohibitive in a single level installation and that it may also be reduced to an acceptable value in the case of a super-structure installation, it then being possible to reduce considerably the mass of the moving parts of'the cable itself, by a judicious disposition of the catapult proper in the immediate neighbourhood of the said guide points.

By way of example, two constructions-of the invention have been diagrammatically illustrated in the accompanying drawings and referred to in the following description, but it will be understood that these constructions may be modified in their details and completed by any useful accessory devices without departing from the in? vention.

In the drawings:

Figure 1 is a plan view of a construction suitable for use as a single-level installation.

Figures 2 and 3 show respectively, the firstin vertical section along the line IIII of Figure 3,

and the second in plan with parts broken away posed on a platform 2 connected to fixed points A launching track 6 constituted; for example,

by two parallel rails is disposed in the axis of this means I on the ground, which simply requires to be roughly flattened and trimmed, on. which track a launching carriage I "intended to carry the object to be launched(aeroplane, glider in which the device is installed partly on a platform 20 and partly below this plat-form, for example the deck of a ship, the arrangement comprises, suitably anchored below the platform and connected thereto by supports at a propelling mechanism l having a balanced double effect comprising a single working cylinder I and two opposed pistons I A, from which extend the cables M and I5 which, after having traversed the platform through suitable apertures and having beenpassed over the fixed pulleys It, I! having a horizontal axis, pass, before proceeding between the pulleys 8, 9, l3 and II of the carriage 1?, over guide pulleys having a fixed vertical or the like) may run or slide according to the:

case.

The carriage l in question is provided'on each of its two sides with two sets of pulleys which are symmetrically disposed and lie opposite one another, 8 and I0 on one 'side'and 9' and M on the other side respectively.

' From the pulleys I2 and [3 with which the pro pelling device I is provided, extend respectively two'moving sides l4 and I5 of a cable which, after" having been passed over the guide pulleys l6 and H, respectively of two fixed lateral points 58 and I9, join one another in thespace comprised between the four pulleys 8, 9, I6 and ll of the carriage 1. l

' The operation of the arrangement is extremely simple to understand. a v s g It will readily be seen, in fact, that when the propelling mechanism I exerts a pull on the cable elements It and IS, the whole of the inner parts M y-Ifi which tends constantly'to shorten, pulls on the carriage l and moves it in the direction of the arrow F according to a movement of which the speed and the acceleration are functions both of the mechanism l and of the distance a which separates the fixed points l8 and 19 from the axis or" the track 6. This action is continued until the instant when, the carriage I arriving in the posinon-1 in which it is shown in dot-and-dash lines inthe drawing, the twosides I 4 l5 are situated in prolongation of one another, which position corresponds in the case under consideration to'theend of the stroke of the driving piston l of-the' propelling system. .From this instant" it is the carriage which, tending by inertia and under the effect of the momentum which it has stored to continue 'to move in order to proceed from the position l to the position 1 (also shown indot-and-dash lines in the drawing), in turn carries along the'cable and forces it to unwind again in spite of the'opposing effort offered to it by the propelling mech anism, for example by the gases which are still enclosed in the cylinder l of the propelling mechanism.

The resistance of the propelling'mechanism I and the inertia of the cable itself ensure in an advantageous manner the progressive breaking and the final stopping of the launching carriage". It willreadily be understood that the fatigue to which the cable is subjected by its stopping at the instant of the passage of the carriage to the position I and its departure in the opposite di-, rection is smaller in proportion as the length a. which separates the fixed points [8 and 19 from the axis of the track is greater.

The judicious choice of this distancepermits of avoiding any cable breakage. In the construction shown in Figures 2 and 3,

axis 2|, 22 or 23, 24, according to the direction in which the cable unwinds.

It is obvious that, by reason of symmetry, such an arrangement can operate both in the direction of the arrow F and in the direction of the arrow F Having now particularly described and ascertained the nature' of my said invention and in what manner the same is to be performed, I declare-that what I claim is:

1. A bow-string catapult device for selectively launching aircraft in either of two opposite directions comprising a launching track, a launching track, a launching carriage movable on said track,- a cable extending transversely of said track, cable guide means disposed onopposite sides of said track at equal distances from the axis thereof, spaced anti-friction means on said carriage for confining'the adjacent cable length therebetween and substantially in the plane of movement of the carriage, said anti-friction means alternately forming oppositely pointing bights in the cable when the carriage moves across a line passing through the respective guide means, a cylinder disposed symmetrically of the track, and at least one'piston slidably mounted in said cylinder and connected to the ends of said cable, whereby movement of said piston or pistons will urge the cable bight portion and attached carriage toward alining position with said guide means, the lengths of'cable between said piston or pistons and the respective guide means being substantially equal.

2. Abow-string catapult device for selectively launching. aircraft in either of two opposite directions comprising a launching track, a launching carriage movable on'said track, a cable extending transversely of said track, cable guide means disposed on opposite sides of said track at equal distances from the axis thereof, spaced pulleys on said carriage for confining the adjacent cable length therebetween and substantially in the plane of movement of the carriage, said pulleys alternately forming oppositely pointing bights in the cable when the carriage moves across a line passin through the respective guide means, a cylinder disposed symmetrically of the track, at least one piston slidably mounted in said cylinder and connected'to the ends of said cable, and a pulley-block system disposed symmetrically of the track and through which said cable passes for multiplyingthe speed of displacement of said piston or pistons, whereby movement of said piston or pistons will urge the cable bight portion and attached carriage toward alining position with said guide (means, the lengths of cable between said pulley. block system and the respective guide means beingv substantially equal.

3. A bow-string catapult device for selectively launching aircraft in either of two opposite directions comprising alaunching track, a launching carriage movable on said track, a cable extending transversely of said track, cable guide means disposed on opposite sides of said track at equal distances from the axis thereof, spaced anti-friction means on said carriage for confining the adjacent cable length therebetween and substantially in the plane of movement of the carriage, said anti-friction means alternately forming oppositely pointing bights in the cable when the carriage moves across a line passing through the respective guide means, a cylinder disposed symmetrically of the track, and a piston slidably mounted in said cylinder and connected to the ends of said cable, whereby movement of said piston will urge the cable bight portion and attached carriage toward alining position with said guide means, the lengths of cable between said piston and the respective guide means being substantially equal.

4. A bow-string catapult device for selectively launching aircraft in either of two opposite directions comprising a launching track, a launching carriage movable on said track, a cable extending transversely of said track, cable guide means disposed on opposite sides of said track at equal distances from the axis thereof, spaced anti-friction means on said carriage for confining the adjacent cable length therebetween and substantially in the plane of movement of the carriage, said anti-friction means alternately forming oppositely pointing bights in the cable when the carriage moves across a line passing through the respective guide means, a cylinder disposed symmetrically of the track, and a pair of pistons mounted in said cylinder and respectively connected to the ends of said cable, whereby movement of said piston will urge the cable bight portion and attached carriage toward alinin position with said guide means, the lengths of cable between said pistons and the respective guide means being substantially equal.

5. A bow-string catapult device for selectively launching aircraft in either of two opposite directions comprising a launching track, a launching carriage movable on said track, means for propelling said carriage along said track including a fixed cylinder and a pair of opposed pistons movable therein, a cable for transmitting the movement of said pistons to said carriage and a pulley-block system associated With said pistons through which said cable passes for multiplying the speed of displacement of said pistons, said propelling means being symmetrically disposed beneath said track at a point intermediate the ends of the latter with the axis of said cylinder and pistons perpendicular to the axis of the track, cable guide means disposed on opposite sides of said track at equal distances from the axis thereof and on a line lying in substantially the same vertical plane as the axis of said propelling means, said cable having its ends connected to the opposed pistons of said propelling means and extending in opposite directions from said propelling means, around said cable guide means and across said track, the lengths of cable between said pistons and the respective guide means being substantially equal, and spaced anti-friction means carried by said carriage for confining the track-crossing portion of said cable therebetween, said last named means and said cable guide means being so constructed and arranged as to alternately form oppositely pointing bights in the cable when the carriage moves across the line on which said cable guide means are disposed and thereby eifectively control the movement of the carriage along the track on both sides of said line.

6. A catapult device according to claim 5 wherein the cable guide means positioned on each side of said track comprises one guide pulley having a horizontal axis parallel to the axis of said track and a pair of similar pulleys having vertical axes positioned closely adjacent said first named pulley between the latter and said track and on opposite sides of the vertical axial plane of said propelling means.

JEAN FIEUX.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,145,685 Chilton Jan. 31, 1939 FOREIGN PATENTS Number Country Date 258,640 Great Britain Sept. 20, 1926 

